On Tuesday--coincidentally, the 30th anniversary of man's first moon landing--Collins will chart a new course for women when she slides into the front left seat of Columbia and takes the controls at liftoff. It will be the first time in 95 space shuttle launches--126 counting Mercury, Gemini, Apollo and Skylab--that a woman is at the helm.

The 42-year-old Air Force colonel will be responsible for four other astronauts, three of them older men.

She'll also be responsible for the heftiest and one of the priciest shuttle payloads ever: NASA's 25-ton, $1.5-billion Chandra X-ray Observatory, on a scientific par with the Hubble Space Telescope. The price tag for the entire Chandra project, from development through five years of orbital operation: $2.8 billion.

Is Collins nervous? No.

"You've got to have the attitude that 'I am confident enough to handle anything,' " says the former test pilot, who has logged more than 5,000 hours in 30 types of aircraft. "I have a lot of faith in God. That's another thing I think that goes a long way."

Does she feel the pressure? You bet. But she doesn't dwell on it.

"Every time my brain starts going in that direction, I stop myself and go, 'Eileen, you're not focusing on the mission. Focus on the mission.' "

And she has, for 1 1/2 years.

Her promotion from shuttle pilot to shuttle commander was announced by Hillary Rodham Clinton at a White House ceremony in March 1998, a few months after NASA gave her the prestigious five-day mission to deliver the telescope to orbit.

"There are a lot of young girls who need to see Eileen in the commander's seat achieving her dreams," says Air Force Lt. Col. Catherine "Cady" Coleman, 38, who is on Collins' crew. "Not so that they can all be astronauts, because then the line to go to space would be way too long, but because they realize that they can achieve their dreams if they work for them."

Collins worked exceedingly hard to achieve hers.

The second of four children, she grew up in public housing in Elmira, N.Y. Her father recalls how he'd take the family to a local airfield to watch gliders and small planes; they could afford little else.

Good at math, Collins considered teaching. Her father suggested accounting. But the images of gliders and planes stuck. She took odd jobs to pay for flying lessons and, with the help of loans and scholarships, aimed for an Air Force career.

Collins graduated from Syracuse University with a bachelor's degree in math and economics in 1978, the same year NASA accepted its first female astronauts. With her sights on space, she trained as an Air Force pilot, then served as a T-38 and C-141 instructor pilot.

After teaching math and instructing T-41 pilots at the U.S. Air Force Academy, Collins became the second woman to enter Air Force Test Pilot School. That same year, 1989, she applied to become an astronaut. A year later, NASA chose her as its first female shuttle pilot.

In February 1995, Collins made her debut as the second-in-command pilot of Discovery. The afterglow was short-lived; one month after the mission, someone threatened to kill her at a parade planned in her honor in Elmira. She skipped the parade. The perpetrator was never caught.

She took a six-week maternity leave following Bridget's birth in November 1995, then flew again as a shuttle pilot to Mir 1 1/2 years later. By then, strangers in restaurants no longer asked for her autograph.

"I know this is going to start happening again," she says. "But it will pass."

For now, though, the spotlight is on.

Women in aerospace and aviation will converge on Kennedy Space Center for Collins' middle-of-the-night launch. Sally Ride, who became the first American woman in space in 1983, will be there, too, with a dual interest.

Ride's former husband, astronaut Steven Hawley, 47, will rocket into orbit with Collins. He was on the astronaut-selection board that chose Collins.

"Although this is a new and important step, in some sense it's a natural evolution," says Hawley. He points to the numbers as evidence: Of the 283 people who have flown on U.S. spacecraft, 32 have been women. (NASA does not count the three rookies killed aboard Challenger in 1986.) Of NASA's current 118 astronauts, 29 are women. Of NASA's 40 shuttle pilots, three are women.

NASA's egalitarian boss, Daniel Goldin, is unfazed: "Eileen Collins is the commander. So what's the news?"